Help with Time? Please....

I run cross country and have made a program to calculate the splits for my times, for instance if I run 3 miles in 17:33 I would put in the minutes and seconds and it would tell me how long it took me to run per mile.

Currently my math function that I wrote, takes in minutes and seconds as seperate int variables and performs some really long and drawn out math on them. This works, but sometimes my split times are only accurate within 2 seconds or so because of the int varables, I couldn't figure out how to do it with double variables.

I know about CTime but do not know how to use it, could you please tell me how to declare a CTime variable with minutes = 17 and seconds = 30, then divide that by three and store in a new variable for output, or at least tell me how to divide minutes and seconds precisley, like up to two decimals.

Thanks,

RunXC410.